Coupling arrangement



July 7, 1964 c. w. ANDERSEN COUPLING ARRANGEMENT 2 Sheets-Sheet 1 Filed March 22, 1962 INVENTOR. Cid/ 07 d d4 firzazr erz U/4w), Mm

y 1964 c. w. ANDERSEN 3,139,732

COUPLING ARRANGEMENT Filed March 22, 1962 2 Sheets-Sheet 2 I NVEN TOR.

United States Patent 3,139,782 COUPLING ARRANGEMENT Ciilford W. Andersen, De Kalb, Ill., assignor to The Wurlitzer Company, Chicago, Ill., a corporation of Ohio Filed Mar. 22, 1962, Ser. No. 181,601 13 Claims. (Cl. 84-240) This invention relates generally to pianos and analogous musical instruments and relates more particularly to coupling arrangements for use therein. 7

As is well known, the action mechanisms employed in both mechanical and electronic pianos and in analogous musical instruments incorporate numerous coacting parts; and in the past, various types of coupling arrangements have been incorporated in these mechanisms. For example, action mechanisms have been connected to their respective key levers in drop-type arrangements by providing a bore in the rear of the key lever. After the free end of a lifter rod has been passed through this bore, a nut or similar element is secured to the end of the rod over the top of the key lever. More recently, this scheme has been supplanted by assembling a fork to the end of the key lever and by securing a rubber grommet to the end of the lifter rod, the rod being releasably secured to the key lever by inserting the grommet in a keyhole-shaped notch opening from the end of the fork. This arrangement, while affording a certain facility in assembly and disassembly of the lifter rod and the key lever, has proved susceptible of incurring objectionable play or looseness in the overall connection.

Therefore, an important object of the present invention is to provide a coupling arrangement which positively interconnects a piano action lifter rod and its operating key lever.

A more general object of the invention is to provide a new and improved coupling arrangement for use in pianos and analogous musical instruments.

Another object of the invention is to provide a coupling arrangement which incorporates a spring grip of one of the coupled members.

Still another object of the invention is to provide a coupling arrangement which reduces the number of parts which must be handled in'final assembly of the musical instrument.

Additional objects and features of the invention pertain to the particular structure and arrangements whereby the above objects are attained.

A coupling arrangement is accord with the invention includes a lever fulcrumed intermediate its ends for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of the lever; and connecting means fixed t0 the lever and extending therefrom into coupling relationship with the link, including a rigid, bifurcated member secured to the lever and a tough, resilient member fixed to the rigid member.

The invention, both to its structure and mode of utilization, will be better understood by reference to the following disclosure and drawings forming a part thereof, wherein;

FIG. 1 is a central sectional view taken through a piano and showing a key lever and an action mechanism coupled in compliance with the invention;

FIG. 2 is an enlarged, side elevational view showing the coupling arrangement of FIG. 1;

FIG. 3 is a view on an enlarged scale taken along the section 33 of FIG. 2;

FIG. 4 is an enlarged, fragmentary view in partial cross section similar to FIG. 3 and illustrating details of the coupling arrangement;

FIG. 5 is an enlarged view taken along the section 5-5 of FIG. 2;

3,139,782 Patented July 7, 1964 FIG. 6 is a View similar to the showing of FIG. 2 but disclosing a modified embodiment of the invention;

FIG. 7 is an enlarged perspective view of the connecting means of the coupling arrangement of FIG. 6;

FIG. 8 is a perspective view of the bifurcated member used in the coupling arrangement of FIG. 6;

FIG. 9 is a perspective View of the tough member which is to be fixed to the bifurcated member of FIG. 8;

FIG. 10 is an enlarged view taken through the section 10-10 of FIG. 7;

FIG. 11 is a view similar to the showing of FIG. 6 but illustrating a still further modified embodiment of the invention;

FIG. 12 is an enlarged perspective view of the connecting means used in the coupling arrangement of FIG. 11; 7

FIG. 13 is a perspective view of the bifurcated member used in the coupling arrangement of FIG. 11; and

FIG. 14 is an enlarged View taken through section -1414 of FIG. 12.

7 Referring now in'detail to the drawings, specifically to FIG. 1, a piano structure indicated generally by the numeral 20 is seen to include a horizontal keybed 22 and a vertical back plate 24. In accordance with conventional practice, piano strings such as piano string 26 are suitably stretched from back plate 24. A keyboard 28 is mounted on the keybed 22, and a balance rail 30 is superpositioned on the keyboard 28 whereby to support an appropriate number of wooden piano key levers such as piano key lever 32. Pins 34 advantageously operated in guide bores formed in the key lever to cooperate with the upper surface of balance rail 30 in defining a fulcrum for the key lever. A keybed felt 36 is suitably secured to the end of a keyboard 28 in order to support the rear end of the key lever in a cushioned manner.

Manual depression of the outer end of key lever 32 is arranged to result in a striking of the corresponding piano string 26 through a piano action indicated generally by the numeral 38. The piano action 38 is mounted in the piano structure by means of a suitable number of action brackets 40, each of which is fastened to the back plate 24 by means of a screw 42 and a tubular, action spacer 44. An action rail 46, a lower supporting rail 48 and a hammer rail 50 extend longitudinally through the body of the piano structure to be aflixed to each of the action brackets 40 for purposes of supporting the individual action units.

In the illustrated embodiment, each of the individual action units includes a felt covered hammer 52, a damper 54 and a back check 56 which is supported on a wippen 53. The wippen 53 is pivoted at 60 relative to the action rail 46 employing a flange in the manner customary. Moreover, a jack 62 is pivotally mounted on the wippen 58 for driving engagement with the butt of hammer 52.

Motion is transmitted to the wippen 58 by means of an endwise reciprocable link or sticker 66 which is juxtaposed with the rear end of key lever 32. The lower end of link 66 terminates in a foot 68 which extends beneath the wippen 58 in alignment therewith for operative engagement with the underside thereof. A link 70 is pivotally connected to foot 68 and to a flange 72 mounted on the lower rail 48 in order to direct the transmission of movement from link 66 to the wippen 58.

A screw element 74 threadedly engages the upper, free end of link 66, the link being preferably fabricated from wood or other similar material to facilitate connection of the screw element therewith; and in order to complete the mechanical path from lever 32 to the piano action, a connecting unit 76 is provided to couple the key lever 32 and the screw element 74. 1

Turning to FIGS. 2-5, the connecting unit 76 is seen to include a relatively rigid, bifurcated member 78 which is firmly mounted to the rear end of key lever 32 as by having a stem portion 8% driven directly into the end of the key lever. Advantageously, a small guide bore is preliminarily drilled into the end of the key lever to insure proper angulation of the rigid member '78. With particular reference to FIG. 3, the stem portion 811 is seen to comprise an elongated member doubled upon itself to form spaced apart legs 82 and an interconnecting bight 84, the legs 82 being spaced in order pressuringly to engage the material of key lever 32. As will be recognized, the surfaces of legs 82 may be mutilated to define barbs in order to further the positive attachment of the member 78 to the key lever.

The rigid, bifurcated member 78 also includes opposed and resiliently spreadable tines 86 which merge individually into the legs 82; and in order to establish proper resiliency in the tines 86 and in the legs 82, the member 78 is fashioned from a spring wire material.

In accordance with an important feature of the invention, a coating 88 of tough, friction material is applied to the surfaces of the tines 86 as is particularly well shown in FIG. 4. The material which is coated on the tines 86 may comprise a suitable resinous plastic material such as a vinyl resin applied as a solvent solution, as a hot melt, as an organisol or as a plasticol. This coating material may also comprise an elastomeric substance such as natural rubber which is dip-coated or electrodeposited as an unvulcanized composition and which is thereafter cured in place. Customarily employed bonding agents have been used to advantage in obtaining proper adherence of the coating to the metal tines. The basic requirements of the coating 83 are that it be resilient and flexible enough to prevent noisy action of the connecting unit, and that it be tough enough to resist the blows required in driving the member 7 3 into the key lever and that it be tough enough to resist the Wear encountered in usage.

The tough, friction material of coating 88 is arranged to define a medial aperture 1% and a spreadable slot 92 communicating the aperture outwardly thereof. Specifically, the tines S are formed with semicircular portions 94, and diverging tips 96 in order to develop the desired aperture and slot in the coating 38.

In order to restrict possible movement of the connecting unit 76 longitudinally of the screw element 74 after coupling thereof, the screw element is provided with a head 98 and a shoulder-defining, radial protuberance Iltld spaced axially apart from the head d8. As is well shown in FIG. 5, the coated tines of the rigid, bifurcated member 78 receive the shank portion of screw element 74 that is defined between head $8 and protuberance 1%. Specifically, the portions 94 of the tines 8% receive the shank portion in a spring grip estab ished by the relative dimensions of the shank portion and the aperture 911 in cooperation with the physical properties present by virtue of fabrication of the element 78 from a spring material. I-lead may be provided with a slot 102 or may be provided in hexagonal shape in order to facilitate connection of the screw element and the link 66. Furthermore, the shoulder-defining protuberance 1% may be replaced with suitable knurling.

The particular embodiment of the invention which has been thus far shown and described does not totally delimit the scope of the invention. Various modifications are contemplated. For example and with reference to FIGS. 6-10 inclusive, a key lever 132 is shown coupled to a link 166 by means of a screw element 174 and a connecting unit 176. Specifically, the screw element 174 threadedly engages an end of the link 1166, and the connecting unit 176 includes a rigid, bifurcated member 178 having a stern portion 181? which is used in piercingly attaching the bifurcated member at the rear end of the key lever.

As will be seen from an inspetcion of FIG. 8, the bifurcated member 178 includes spaced apart, parallel arms 182 and 184 which are interconnected and coupled to stem 181) by a strut 1186. Elements 1182, 184, and 186 define a rectangular open region 183; and a tough, re-

silient member 1% is fastened to the member 173 in the open region 188 as shown in FIG. 7. Turning to FIG. 9, the resilient member 1% is seen to include lateral parallel grooves 1E2 and 194; and these grooves are adapted to receive the arms 182 and 184 respectively with the ends 195 of the arms exposed as by being flush with the adjacent surface of the member 191} as is shown in FIG. 7.

The tough, resilient member 1% is arranged to define a medial aperture 196 which perforates the member, further defining a spreadable slot 198 communicating aperture 1% with the boundary edge of the member whereby resiliently to pass an axial portion of screw element 174. Slot 198 may be incised in the member 190 after vulcanization or it may be molded into the member 190 during production of the same.

In accordance with the embodiment of FIGS. 6-10, the member 190 is arranged to be permanently attached to the bifurcated member 178 prior to assembly of the bifurcated member with key lever 132. Specifically, the member 191 is selected to be fabricated from an elastomeric material which is molded to the bifurcated member 178 or bonded thereto with a suitable adhesive material after vulcanization. The ends 195 of the arms 182 and 1&4- are exposed as shown in FIG. 7 in order that the connecting unit 176 can be readily driven into the end of key lever 132 after the member 190 has been permanently attached to the bifurcated member 178.

Returning to FIG. 6, the medial aperture 196 of resilient member 198! is seen to receive an axial portion of screw element 174 between a head 198 and a shoulderdefining protuberance 2% formed thereon, head 1% and protuberance Ztltl restricting movement of the resilient member axially of the link 1&6.

Whereas the member 191 is shown in FIGS. 610 as being fabricated as a rectangular parallelepiped, the resilient member may take other advantageous shapes. Similarly, the bifurcated member 178 and the means for permanently attaching the resilient member and the bifurcated member are subject to variations. Accordingly, a further modified embodiment of the invention is shown in FIGS. 11-14 wherein similar numerals to those used in FIGS. 6-10 have been employed to designate like parts, the suffix letter a being employed to distinguish those elements associated with the embodiment of FIGS. 11-14.

The embodiment of FIGS. 11-14 is distinguished in that the resilient member 1%a is fashioned in generally cylindrical shape whereby to be provided with a continuous lateral groove 2.192 for receiving arms 182a and 184:: and strut 186a. correspondingly, open region 188a is fashioned with a curvilinear end defined by strut 186a in order fittingly to engage the floor of groove 2112. It will also be apparent that slot 198a is divided by the groove 202 as will be seen in FIG. 12, the slot 198a being arranged to be somewhat wider than the slot 1% provided in the embodiment illustrated in FIGS. 6-10.

In addition, barbs 21% are raised from the upper and lower surfaces of arms 182a and 184a as will be seen in FIGS. 11 and 13. These barbs are provided in order to retain a previously vulcanized member 196a in fixed attachment to the bifurcated member 178a upon assembly thereto.

In other respects, the embodiment of FIGS. 11-14 is similar to the embodiment of FIGS. 6-10.

While particular embodiments of the invention have been shown and described, it should be understood, of course, that the invention is not strictly limited thereto. Numerous changes will, no doubt, occur to those skilled in the art; and these changes are to be understood as forming a part of this invention insofar as they fall within the spirit and scope of the appended claims.

The invention is claimed as follows:

1. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means extending from said lever into coupling relationship with said link, including opposed tines embracing said link, said tines being resiliently spreadable whereby to facilitate coupling and decoupling of said lever and said link; and tough, friction material acting between said tines and said link for use in coupling said link to said lever.

2. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means extending from said lever into coupling relationship with said link, including opposed tines embracing said link, said tines being resiliently spreadable whereby to facilitate coupling and decoupling of said lever and said link; and tough, friction material coated on one of said link and said connecting means for use in coupling said link to said lever.

3. A coupling arrangement according to claim 1 wherein said tines are fashioned from spring material.

4. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed intermediate its ends for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means extending from said lever into coupling relationship with said link, including opposed tines embracing said link, said tines being resiliently spreadable whereby to facilitate coupling and decoupling of said lever and said link; tough, friction material acting between said tines and said link for use in coupling said link to said lever; and means on said link for restricting movement of said tines longitudinally thereof.

5. A coupling arrangement for use in pianos and analogous musical instruments comprising: a wooden lever fulcrumed for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means extending from said lever into coupling relationship with said link, including opposed tines embracing said link, said tines being resiliently spreadable whereby to facilitate coupling and decoupling of said lever and said link and an elongated member interconnecting said tines and adapted to be driven into said lever for afiixing said connecting means thereto; and tough, friction material coated on one of said link and said connecting means for use in coupling said link to said lever.

6. A coupling arrangement acocrding to claim 5 wherein said elongated member is doubled upon itself with the resultant leg portions disposed in spaced apart relationship.

in said friction material is a resinous plastic.

8. A coupling arrangement according to claim 1 wherein said friction material is an elastomer.

9. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed intermediate its ends for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means fixed to said lever and extending therefrom into coupling relationship with said link, including a rigid, bifurcated member secured to said lever and a tough, resilient member fixed to said rigid member, said tough member defining a medial aperture and a spreadable slot communicating said aperture outwardly thereof whereby resiliently to pass an axial portion of said link for retention by said means, said tough member having opposed lateral grooves for receiving the arms of said bifurcated member, whereby to lock said tough member against movement relative to said lever in the direction axially of said link; and radial enlarge- 7. A coupling arrangement according to claim 1 where- 10. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed intermediate its ends for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means fixed to said lever and extending therefrom into coupling relationship with said link, including a rigid, bifurcated member having a stem portion axially piercingly attached to said lever and a tough, resilient member fixed to said rigid member, said tough member defining a medial aperture perforating the member and further defining a spreadable slot communicating said aperture with the boundary edge of the member whereby resiliently to pass an axial portion of said link for retention by said means, said tough member having opposed lateral grooves for receiving the arms of said bifurcated member, whereby to lock said tough member against movement relative to said link in the direction axially of said link; and radial enlargement of greater diameter than said aperture on said link disposed respectively at the opposite ends of said axial portion and spaced to receive said tough member therebetween for restricting movement of said tough member axially of said link,

whereby to couple said link to said lever.

11. A coupling arrangement according to claim 10 wherein the branches of said bifurcated member have ends extending at least to the edge of said tough member whereby to be exposed for access in driving said bifurcated member into piercingly attached relationship with said lever.

12. A coupling arrangement according to claim 9 which further comprises means acting between said bifurcated member and said tough member to attach said members permanently together.

13. A coupling arrangement for use in pianos and analogous musical instruments comprising: a lever fulcrumed intermediate its ends for transmitting motion to a link; an endwise reciprocable link situated adjacent one end of said lever; connecting means fixed to said lever and extending therefrom into coupling relationship with said link, including a rigid bifurcated member secured to said lever and having spaced arms with parallel confronting edges, said connecting means further including a tough, resilient member fixed to said rigid member, said tough member defining a medial aperture and a spreadable slot communicating said aperture outwardly thereof whereby resiliently to pass an axial portion of said link for retention by said means, said tough member having opposed lateral grooves with parallel root surfaces for slidably receiving said arms at the parallel confronting edges thereof whereby to lock said tough member against movement relative to said lever in the direction axially of said link; and radial enlargements of greater diameter than said aperture on said link disposed respectively at the opposite ends of said axial portion and spaced to receive said tough member therebetween for restricting movement of said tough member axially of said link, whereby to couple said link to said lever.

References Cited in the file of this patent UNITED STATES PATENTS 2,164,803 Duraffourg July 4, 1939 2,207,197 Havey July 9, 1940 2,417,666 Socin Mar. 18, 1947 3,040,614 Behning June 26, 1962 

1. A COUPLING ARRANGEMENT FOR USE IN PIANOS AND ANALOGOUS MUSICAL INSTRUMENTS COMPRISING: A LEVER FULCRUMED FOR TRANSMITTING MOTION TO A LINK; AN ENDWISE RECIPROCABLE LINK SITUATED ADJACENT ONE END OF SAID LEVER; CONNECTING MEANS EXTENDING FROM SAID LEVER INTO COUPLING RELATIONSHIP WITH SAID LINK, INCLUDING OPPOSED TINES EMBRACING SAID LINK, SAID TINES BEING RESILIENTLY SPREADABLE WHEREBY TO FACILITATE COUPLING AND DECOUPLING OF SAID LEVER AND SAID LINK; AND TOUGH, FRICTION MATERIAL ACTING BETWEEN SAID TINES AND SAID LINK FOR USE IN COUPLING SAID LINK TO SAID LEVER. 